Spectacle lens and spectacles

ABSTRACT

The spectacle lens includes a lens substrate including a blue light absorbing compound, and a multilayer film including a metal layer having a film thickness of 1.0 nm to 10.0 nm, wherein a blue light cut ratio is 35.0% or more, an average reflectance in a wavelength range of 400 nm to 500 nm on an object-side surface obtained by measurement from the object side is in a range of 15.00% to 25.00%, and an average reflectance in a wavelength range of 400 nm to 500 nm on an eyeball-side surface obtained by measurement from the object side is less than 2.00%.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of PCT International Application No.PCT/JP2018/036298 filed on Feb. 28, 2018, which was published under PCTArticle 21(2) in Japanese and claims priority under 35 U.S.C § 119(a) toJapanese Patent Application No. 2017-191691 filed on Sep. 29, 2017. Theabove applications are hereby expressly incorporated by reference, intheir entirety, into the present application.

TECHNICAL FIELD

The present disclosure relates to a spectacle lens and spectaclesprovided with the spectacle lens.

BACKGROUND ART

In recent years, CRT monitor screens of digital equipment have beenreplaced by liquid crystal screens, and recently LED liquid crystalshave become widespread, but liquid crystal monitors, especially LEDliquid crystal monitors, strongly emit short-wavelength light calledblue light. Therefore, in order to effectively reduce fatigue of theeyes and eyestrain caused by long-term use of digital equipment,measures should be taken to reduce the burden on the eyes caused by bluelight. Generally, light in the wavelength range of 400 nm to 500 nm orlight in the vicinity of this wavelength range is called blue light.

Regarding the above points, for example, Japanese Patent ApplicationPublication No. 2013-8052 suggests an optical article having amultilayer film featuring selective strong reflection of light with awavelength of 400 nm to 450 nm on both surfaces of a plastic substrate.

SUMMARY

As a means for reducing the burden on the eyes caused by blue light, ina spectacle lens, a multilayer film featuring selective strongreflection of blue light can be provided on both surfaces of a lenssubstrate, as described in Japanese Patent Application Publication No.2013-8052.

However, where a multilayer film featuring selective strong reflectionof blue light is provided on both surfaces of a lens substrate, thewearing feeling of the spectacle lens tends to deteriorate.Specifically, a wearer wearing spectacles provided with such spectaclelenses tends to see a double image called a ghost, and therefore,wearing comfortableness tend to be deteriorated.

An aspect of the present disclosure provides for a spectacle lens thatcan reduce a burden on the eyes caused by blue light and has a goodwearing feeling.

One aspect of the present disclosure relates to

a spectacle lens having

a lens substrate including a blue light absorbing compound, and

a multilayer film including a metal layer having a film thickness of 1.0nm to 10.0 nm, wherein

a blue light cut ratio is 35.0% or more,

an average reflectance in a wavelength range of 400 nm to 500 nm on anobject-side surface obtained by measurement from the object side is in arange of 15.00% to 25.00%, and

an average reflectance in a wavelength range of 400 nm to 500 nm on aneyeball-side surface obtained by measurement from the object side isless than 2.00%.

The blue light cut ratio of the spectacle lens is 35.0% or more. Sincethe blue light can be blocked with such a high blue light cut ratio, thespectacle lens makes it possible to reduce the quantity of blue lightentering the eyes of the wearer of the spectacles provided with thisspectacle lens, thereby reducing the burden on the eyes of the wearercaused by light.

The following features can mainly contribute to the realization of theblue light cut ratio of 35.0% or more,

(i) the lens substrate includes a blue light absorbing compound,

(ii) the average reflectance in the wavelength range of 400 nm to 500 nmon the object-side surface obtained by measurement from the object sideis in the range of 15.00% to 25.00%, and

(iii) the lens has a multilayer film including a metal layer having afilm thickness of 1.0 nm to 10.0 nm.

Regarding (iii), since a metal has the property of absorbing light inthe visible range, the metal can also absorb blue light. This cancontribute to increasing the blue light cut ratio of the spectacle lens.Further, when the metal layer is made thick, the transmittance (forexample, luminous transmittance) of the spectacle lens is largelyreduced, but in the case of the metal layer having a film thickness of1.0 nm to 10.0 nm, the transmittance of the spectacle lens can beprevented from being greatly reduced.

The main cause of the occurrence of a ghost (double image) in thespectacle lens provided with a multilayer film having the property ofselectively and strongly reflecting the blue light on both surfaces ofthe lens substrate is conceivably that the blue light incident on theinside of the spectacle lens without being reflected on the object-sidesurface of the spectacle lens undergoes multiple reflection between bothsurfaces provided with the multilayer film having the property ofstrongly reflecting the blue light inside the spectacle lens. Meanwhile,because of the above-described features (i) to (iii), the spectacle lenscan realize a blue light cut ratio of 35.0% or more without requiringstrong selective reflection of blue light on the eyeball-side surface ofthe lens substrate. As a result, the intensity with which the ghost(double image) formed by multiple reflection of the blue light insidethe spectacle lens is visually perceived can be reduced or the intensitycan be reduced so as not to be visually recognizable.

Another aspect of the present disclosure relates to spectacles providedwith the spectacle lens.

According to the aspects of the present disclosure, it is possible toprovide a spectacle lens that can reduce the burden on the eyes causedby blue light and that has a good wearing feeling, and also to providespectacles provided with the spectacle lens.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a reflection spectroscopic spectrum (measured from the objectside) obtained for the spectacle lens of Example 1.

FIG. 2 is a reflection spectroscopic spectrum (measured from the objectside) obtained for the spectacle lens of Example 2.

DESCRIPTION OF EMBODIMENTS

[Spectacle Lens]

A spectacle lens according to one aspect of the present disclosure has alens substrate including a blue light absorbing compound, and amultilayer film including a metal layer having a film thickness of 1.0nm to 10.0 nm, wherein a blue light cut ratio is 35.0% or more, anaverage reflectance in a wavelength range of 400 nm to 500 nm on anobject-side surface obtained by measurement from the object side is in arange of 15.00% to 25.00%, and an average reflectance in a wavelengthrange of 400 nm to 500 nm on an eyeball-side surface obtained bymeasurement from the object side is less than 2.00%.

Definitions of terms and/or measurement methods of the presentdisclosure will be described hereinbelow.

The “object-side surface” is a surface located on the object side whenspectacles provided with spectacle lenses are worn by the wearer, andthe “eyeball-side surface” is a surface located on the opposite side,that is, on the eyeball side when spectacles provided with spectaclelenses are worn by the wearer. Regarding the surface shape, in oneembodiment, the object-side surface is convex and the eyeball-sidesurface is concave. However, the present disclosure is not limited tothis embodiment.

The “blue light absorbing compound” refers to a compound havingabsorption in the wavelength range of 400 nm to 500 nm.

The “blue light cut ratio” is obtained according to following Equation 1according to the standard of the Japan Medical-Optical EquipmentIndustrial Association.

Blue light cut ratio C _(b)=1−τ_(b)  (Equation 1)

In Equation 1, τ_(b) is a weighted transmittance of blue light harmfulto eyes that is stipulated by the standard of the Japan Medical-OpticalEquipment Industrial Association, and is calculated by followingEquation 2. In Equation 2, WB(λ) is a weighting function and iscalculated by following Equation 3. τ(λ) is the transmittance at thewavelength λ nm measured by a spectrophotometer. Therefore, the cutratio of blue light by absorption and the cut ratio of blue light byreflection are added in the blue light cut ratio C_(b).

$\begin{matrix}{\tau_{b} = \frac{\int_{380\; {nm}}^{500\; {nm}}{{{\tau (\lambda)} \cdot {{WB}(\lambda)} \cdot d}\; \lambda}}{\int_{380\; {nm}}^{500\; {nm}}{{WB}{(\lambda) \cdot d}\; \lambda}}} & \left( {{Equation}\mspace{14mu} 2} \right) \\{{{WB}(\lambda)} = {{E_{S\; \lambda}(\lambda)} \cdot {B(\lambda)}}} & \left( {{Equation}\mspace{14mu} 3} \right)\end{matrix}$

In Equation 3, E_(sλ)(λ) is the spectral irradiance of sunlight, andB(λ) is a blue light hazard function. E_(sλ)(λ), B(λ) and WB(λ) aredescribed in Annex C of JIS T 7333. When values are calculated usingE_(sλ)(λ), B(λ) and WB(λ), the measurement with a spectrophotometer isperformed at least from 380 nm to 500 nm at a measurement wavelengthinterval (pitch) of 1 nm to 5 nm.

The average reflectance in the wavelength range of 400 nm to 500 nm onthe object-side surface obtained by measurement from the object side ofthe spectacle lens is an average reflectance on the object-side surfacewith respect to the light directly incident from the object side (thatis, the incident angle is 0°) and is an arithmetic average of thereflectance measured on the object-side surface in the wavelength rangeof 400 nm to 500 nm by using a spectrophotometer from the object side ofthe spectacle lens. The average reflectance in the wavelength range of400 nm to 500 nm on the eyeball-side surface obtained by measurementfrom the object side of the spectacle lens is an average reflectance onthe eyeball-side surface with respect to the light directly incidentfrom the object side and is an arithmetic average of the reflectancemeasured on the eyeball-side surface in the wavelength range of 400 nmto 500 nm by using a spectrophotometer from the object side of thespectacle lens. Hereinafter, the average reflectance in the wavelengthrange of 400 nm to 500 nm is also referred to as “blue lightreflectance”.

Further, the blue light reflectance on the eyeball-side surface obtainedby measurement from the eyeball side, which is described hereinbelow, isan average reflectance on the eyeball-side surface with respect to thelight directly incident from the eyeball side and is an arithmeticaverage of the reflectance on the eyeball-side surface in the wavelengthrange of 400 nm to 500 nm, which is measured from the eyeball-side ofthe spectacle lens using a spectrophotometer. The blue light reflectanceon the object-side surface obtained by measurement from the eyeballside, which is described hereinbelow, is an average reflectance on theobject-side surface with respect to the light directly incident from theeyeball side (that is, the incident angle is 0°) and is the arithmeticaverage of the reflectance measured on the object-side surface in thewavelength range of 400 nm to 500 nm by using a spectrophotometer fromthe eyeball side of the spectacle lens.

In measurement by a lens reflectance measuring device (for example,USPM-RU manufactured by Olympus Corporation), by aligning the focalposition with the measurement target surface (object-side surface oreyeball-side surface), it is possible to measure the reflectance on theobject-side surface and the reflectance on the eyeball-side surface withrespect to the light incident from the same direction. Also, in themeasurement, the measurement wavelength interval (pitch) can bearbitrarily set. For example, the measurement wavelength interval can beset in the range of 1 nm to 5 nm.

The “main wavelength” to be described hereinbelow is an index obtainedby digitizing the wavelength of light color felt by the human eye and ismeasured in accordance with Annex JA of JIS Z 8781-3:2016.

The “luminous reflectance” to be described hereinbelow is measured inaccordance with JIS T 7334:2011, and the “luminous transmittance” ismeasured in accordance with JIS T 7333:2005.

The “YI (Yellowness Index) value” to be described hereinbelow ismeasured in accordance with JIS K 7373:2006. The YI value is a numericalvalue indicating yellow strength. The higher the YI value, the strongerthe yellowish color.

In the present disclosure and the present description, “film thickness”is a physical film thickness. The film thickness can be obtained by awell-known film thickness measurement method. For example, the filmthickness can be obtained by converting the optical film thicknessmeasured by the optical film thickness measuring device into thephysical film thickness.

Hereinafter, a multilayer film including a metal layer with a filmthickness of 1.0 nm to 10.0 nm is also described as “a multilayer filmincluding a metal layer”, and another multilayer film is also describedas “another multilayer film”.

Hereinafter, the spectacle lens will be described in greater detail.

<Blue Light Cut Ratio>

The blue light cut ratio of the spectacle lens is 35.0% or more. Withthe spectacle lens having the blue light cut ratio of 35.0% or more,where the wearer wears spectacles provided with such a spectacle lens,the quantity of blue light entering the eyes of the wearer can bedecreased and the burden on the eyes of the wearer caused by the bluelight can be reduced. The blue light cut ratio may be 36.0% or more,37.0% or more, or 38.0% or more. Further, the blue light cut ratio canbe, for example, 80.0% or less, 60.0% or less, 50.0% or less, or 45.0%or less. However, from the viewpoint of reducing the quantity of bluelight incident on the eyes of the wearer, a blue light cut ratio can behigher, so the upper limit exemplified above may be exceeded.

<Blue Light Reflectance>

In the spectacle lens, the blue light reflectance on the eyeball-sidesurface obtained by measurement from the object side of the spectaclelens is less than 2.00%. As described above, when a multilayer filmhaving the property of selectively and strongly reflecting blue light isprovided on both surfaces of a lens substrate, wearing feeling of thespectacle lens deteriorates. Meanwhile, according to the above (i) to(iii), the blue light cut ratio of 35.0% or more can be realized withoutrequiring an increase in the blue light reflectance on the eyeball-sidesurface of the spectacle lens. As a result, deterioration of wearingfeeling of the spectacle lens due to occurrence of a ghost (doubleimage) can be suppressed. From the viewpoint of further suppressing theoccurrence of a ghost, the blue light reflectance on the eyeball-sidesurface obtained by measurement from the object side of the spectaclelens may be 1.50% or less, or 1.00% or less. Further, the blue lightreflectance on the eyeball-side surface obtained by measurement from theobject side of the spectacle lens can be, for example, 0.10% or more or0.20% or more. However, from the viewpoint of suppressing the occurrenceof a ghost, since the blue light reflectance on the eyeball-side surfaceobtained by measurement from the object side of the spectacle lens maybe low, the blue light reflectance may be lower than the lower limitexemplified hereinabove.

The reason why the blue light reflectance on the eyeball-side surface ismeasured from the object side on the opposite side to the eyeball sideis that it is conceivable that the blue light reflectance measured fromthe object side is more influential than the blue light reflectancemeasured from the eyeball side with respect to multiple reflection ofthe light incident from the object side inside the spectacle lens.

Meanwhile, the blue light reflectance on the object-side surfaceobtained by measurement from the object side of the spectacle lens is15.00% or more and 25.00% or less. The fact that the blue lightreflectance is 15.00% or more can contribute to increasing the bluelight cut ratio of the spectacle lens by reflecting the blue lightincident from the object side. From this viewpoint, the blue lightreflectance on the object-side surface obtained by measurement from theobject side of the spectacle lens may be 16.00% or more, 16.50% or more,or 17.00% or more. In addition, the fact that the blue light reflectanceon the object-side surface obtained by measurement from the object sideof the spectacle lens is 25.00% or less can contribute to suppressingthe occurrence of a ghost (double image). From this viewpoint, the bluelight reflectance on the object-side surface obtained by measurementfrom the object side of the spectacle lens may be 23.00% or less, or20.00% or less.

The features of the lens substrate including a blue light absorbingcompound ((i) hereinabove) and the spectacle lens having a multilayerfilm including a metal layer as one layer in the multilayer film(multilayer film including as metal layer) ((iii) hereinabove) can alsocontribute to the fact that the spectacle lens exhibits a blue light cutratio of 35.0% or more without requiring an increase in the blue lightreflectance on the eyeball-side surface of the spectacle lens. The lenssubstrate and multilayer film including a metal layer will be describedhereinbelow in detail.

<Lens Substrate>

The lens substrate included in the spectacle lens is not particularlylimited as long as the substrate includes a blue light absorbingcompound. The lens substrate can be a plastic lens substrate or a glasslens substrate. The glass lens substrate can be made, for example, ofinorganic glass. A plastic lens substrate may be lightweight and hard tobreak and a blue light absorbing compound can be easily introducedtherein. The plastic lens substrate can be exemplified by a styreneresin such as a (meth)acrylic resin, a polycarbonate resin, an allylresin, an allyl carbonate resin such as diethylene glycol bis-allylcarbonate resin (CR-39), a vinyl resin, a polyester resin, a polyetherresin, an urethane resin obtained by reacting an isocyanate compoundwith a hydroxy compound such as diethylene glycol, a thiourethane resinobtained by reacting an isocyanate compound with a polythiol compound,and a cured product (generally referred to as a transparent resin)obtained by curing a curable composition including a (thio)epoxycompound having one or more disulfide bonds in a molecule. The curablecomposition can also be referred to as a polymerizable composition. Anot-dyed lens substrate (colorless lens) and a dyed substrate (dyedlens) may be used. The refractive index of the lens substrate can be,for example, about 1.60 to 1.75. However, the refractive index of thelens substrate is not limited to the above range, and may be separatedupward and downward from the above range even within the above range. Inthe present disclosure and the present description, the refractive indexrefers to the refractive index for the light having a wavelength of 500nm. In addition, the lens substrate may be a lens having refractingpower (so-called prescription lens) or a lens without refracting power(so-called non-prescription lens).

The spectacle lens can be of a variety of types such as a single focuslens, a multifocal lens, a progressive power lens and the like. The typeof the lens is determined by the surface shape of both sides of the lenssubstrate. Further, the lens substrate surface may be any one of aconvex surface, a concave surface, and a flat surface. In ordinary lenssubstrates and spectacle lenses, the object-side surface is a convexsurface and the eyeball-side surface is a concave surface. However, thepresent disclosure is not limited to such a configuration.

(Blue Light Absorbing Compound)

The lens substrate includes a blue light absorbing compound. This is oneof the reasons why the blue light cut ratio of 35.0% or more can beprovided to the spectacle lens. The blue light absorbing compound can beexemplified by various compounds having absorption in the wavelengthrange of blue light, such as a benzotriazole compound, a benzophenonecompound, a triazine compound, an indole compound and the like. Abenzotriazole compounds may be represented by a following formula (1).

In the formula (1), X represents a group giving a resonance effect. Thesubstitution position of X may be the 5th position in the triazole ring.

Examples of X include a chlorine atom, a bromine atom, a fluorine atom,an iodine atom, a sulfo group, a carboxy group, a nitrile group, analkoxy group, a hydroxy group, and an amino group.

In the formula (1), R₂ represents an alkyl group having 1 to 12 carbonatoms or an alkoxy group having 1 to 12 carbon atoms, and for the alkylgroup and the alkoxy group, the number of carbon atoms may be 1 to 8, 2to 8, or 4 to 8.

The alkyl group and alkoxy group may be branched or linear.

Examples of the alkyl group include a methyl group, an ethyl group, ann-propyl group, an iso-propyl group, an n-butyl group, a sec-butylgroup, a tert-butyl group, a pentyl group, a hexyl group, a heptylgroup, an n-octyl group, a 1,1,3,3-tetramethylbutyl group, a nonylgroup, a decyl group, an undecyl group, a dodecyl group and the like.

Examples of the alkoxy group include a methoxy group, an ethoxy group, apropoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, aheptyloxy group, an octyloxy group, a nonyloxy group, a decyloxy group,an undecyloxy group and a dodecyloxy group.

In the formula (1), the substitution position of R₂ may be 3rd, 4th or5th position based on the substitution position of the benzotriazolylgroup.

In the formula (1), R₁ represents an alkyl group having 1 to 3 carbonatoms or an alkoxy group having 1 to 3 carbon atoms, and specificexamples thereof include those having the appropriate number of carbonatoms among the examples relating to R₂.

In the formula (1), m represents an integer of 0 or 1.

In the formula (1), the substitution position of R₂ may be the 5thposition based on the substitution position of the benzotriazolyl group.

n represents the valence of R₃ and is 1 or 2.

In the formula (1), R₃ represents a hydrogen atom or a divalenthydrocarbon group having 1 to 8 carbon atoms. When n is 1, R₃ representsa hydrogen atom, and when n is 2, R₃ represents a divalent hydrocarbongroup having 1 to 8 carbon atoms.

The hydrocarbon group represented by R₃ can be exemplified by analiphatic hydrocarbon group or an aromatic hydrocarbon group. The numberof carbon atoms of the hydrocarbon group represented by R₃ is 1 to 8,and may be 1 to 3.

Examples of the divalent hydrocarbon group represented by R₃ include amethanediyl group, an ethanediyl group, a propanediyl group, abenzenediyl group, a toluenediyl group and the like.

In the formula (1), the substitution position of R₃ may be the 3rdposition based on the substitution position of the benzotriazolyl group.

R₃ may be a hydrogen atom; in this case, n is 1.

The benzotriazole compound may be a benzotriazole compound representedby a following formula (1-1).

In the formula (1-1), R₁, R₂ and m have the same meanings as definedabove, and the exemplification and embodiments are also the same asthose described above.

Specific examples of the benzotriazole compound represented by theformula (1) includemethylenebis[3-(5-chloro-2-benzotriazolyl)-5-(1,1,3,3-tetramethylbutyl)-2-hydroxyphenyl],methylenebis[3-(5-chloro-2-benzotriazolyl)-5-(tert-butyl)-2-hydroxyphenyl],methylenebis[3-(5-chloro-2-benzotriazolyl)-5-tert-butyl-2-hydroxyphenyl],methylenebis[3-(5-chloro-2-benzotriazolyl)-5-tert-butyl-2-hydroxyphenyl],methylenebis[3-(5-chloro-2-benzotriazolyl)-5-ethoxy-2-hydroxyphenyl],phenylenebis[3-(5-chloro-2-benzotriazolyl-5-(1,1,3,3-tetramethylbutyl)-2-hydroxyphenyl],and the following specific examples of the benzotriazole compoundsrepresented by the formula (1-1).

Specific examples of the benzotriazole compound represented by theformula (1-1) include2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole,2-(3-tert-butyl-2-hydroxy-5-ethylphenyl)-5-chloro-2H-benzotriazole,5-chloro-2-(3,5-dimethyl-2-hydroxyphenyl)-2H-benzotriazole,5-chloro-2-(3,5-diethyl-2-hydroxyphenyl)-2H-benzotriazole,5-chloro-2-(2-hydroxy-4-methoxyphenyl)-2H-benzotriazole,5-chloro-2-(4-ethoxy-2-hydroxyphenyl)-2H-benzotriazole,2-(4-butoxy-2-hydroxyphenyl)-5-chloro-2H-benzotriazole, and5-chloro-2-(2-hydroxy-4-octyloxyphenyl)-2H-benzotriazole.

Specific examples of the benzotriazole compound represented by theformula (1-1) include2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole,2-(3-tert-butyl-2-hydroxy-5-ethylphenyl)-5-chloro-2H-benzotriazole,5-chloro-2-(4-ethoxy-2-hydroxyphenyl)-2H-benzotriazole, and2-(4-butoxy-2-hydroxyphenyl)-5-chloro-2H-benzotriazole.

The above lens substrate may include 0.05 parts by mass to 3.00 parts bymass, 0.05 parts by mass to 2.50 parts by mass, 0.10 parts by mass to2.00 parts by mass, or 0.30 parts by mass to 2.00 parts by mass of ablue light absorbing compound with respect to 100 parts by mass of aresin (or a polymerizable compound for obtaining the resin) constitutingthe lens substrate. However, the amount of the blue light absorbingcompound is not limited to the above ranges, provided that the bluelight cut ratio of the spectacle lens is 35.0% or more. A known methodcan be used for producing a lens substrate including a blue lightabsorbing compound. For example, in a method of curing a curablecomposition to obtain a lens substrate as a lens-shaped molded article,a lens substrate including a blue light absorbing compound can beobtained by adding the blue light absorbing compound to the curablecomposition. Alternatively, a blue light absorbing colorant can beintroduced into a lens substrate by various wet or dry methods generallyused for dyeing a lens substrate. For example, a wet method can beexemplified by a dipping method (immersion method), and a dry method canbe exemplified by a sublimation dyeing method.

In addition, the lens substrate may include various additives which aregenerally included in lens substrates for spectacle lenses. For example,in the case where a lens substrate is formed by curing a curablecomposition including a polymerizable compound and a blue lightabsorbing compound, a polymerization catalyst disclosed in, for example,Japanese Patent Application Publication No. H07-063902, Japanese PatentApplication Publication No. H07-104101, Japanese Patent ApplicationPublication No. H09-208621 and Japanese Patent Application PublicationNo. H09-255781, and one or more additives such as an internal releaseagent, an antioxidant, a fluorescent whitening agent, a bluing agent andthe like disclosed in, for example, Japanese Patent ApplicationPublication No. H01-163012 and Japanese Patent Application PublicationNo. H03-281312 may be added to the curable composition. Known types andamounts of these additives can be used and a known method can be usedfor molding a lens substrate using a curable composition.

<Multilayer Film>

(Multilayer Film Including Metal Layer)

The spectacle lens has a multilayer film including a metal layer havinga film thickness of 1.0 nm to 10.0 nm.

The multilayer film including a metal layer can be located on theobject-side surface of the spectacle lens, can be located on theeyeball-side surface, or can be located on both surfaces. In oneembodiment, the multilayer film including a metal layer is located onone of the eyeball-side surface and the object-side surface of thespectacle lens, and another multilayer film is located on the othersurface. In another embodiment, a multilayer film including a metallayer is located on one of the eyeball-side surface and the object-sidesurface of the spectacle lens, and neither a multilayer film including ametal layer nor another multilayer film is located on the other surface.In one embodiment, from the viewpoint of easiness of controlling theblue light reflectance on the eyeball-side surface that is obtained bymeasurement from the object side of the spectacle lens to be less than2.00%, the multilayer film including a metal layer may be formed on atleast the eyeball-side surface of a spectacle lens, or may be formedonly on the eyeball-side surface. The multilayer film including a metallayer and the other multilayer film may be located directly on thesurface of the lens substrate or may be located indirectly on thesurface of the lens substrate with one or more other layerstherebetween. Examples of the layer that can be formed between the lenssubstrate and the multilayer film include a polarizing layer, a lightcontrol layer, a hard coat layer, and the like. By providing the hardcoat layer, the durability (strength) of the spectacle lens can beenhanced. The hard coat layer can be, for example, a cured layerobtained by curing a curable composition. For details of the hard coatlayer, reference can be made to, for example, paragraphs 0025 to 0028and 0030 of Japanese Patent Application Publication No. 2012-128135. Inaddition, a primer layer for improving adhesion may be formed betweenthe lens substrate and the multilayer film. For details of the primerlayer, reference can be made to, for example, paragraphs 0029 to 0030 ofJapanese Patent Application Publication No. 2012-128135.

In the present disclosure and the present description, the “metal layer”means a film formed by depositing a component selected from the groupconsisting of a single metal element (pure metal), an alloy of aplurality of metal elements, and a compound of one or more metalelements (hereinafter referred to as “metal component”) by an arbitraryfilm formation method, and it is a film composed of a metal component,except for depositing impurities inevitably mixed at the time of filmformation and well-known additives that are used at random to assistfilm formation. For example, the metal layer is a film in which themetal component accounts for 90% by mass to 100% by mass with respect tothe mass of the film, and may be a film in which the metal componentaccounts for 95% by mass to 100% by mass. The metal element can beexemplified by a transition element such as a chromium group element(for example, Cr, Mo, and W), an iron group element (for example, Fe,Co, and Ni), a noble metal element (for example, Cu, Ag, and Au).Specific embodiments of the metal layer include, for example, a chromiumlayer, a nickel layer and a silver layer. The metal component containedin the chromium layer can be single chromium (that is, metallic Cr),chromium oxide, or a mixture thereof. The metal component contained inthe nickel layer can be single nickel (that is, metallic Ni), nickeloxide, or a mixture thereof. The metal component contained in the silverlayer can be single silver (that is, metallic Ag), silver oxide, or amixture thereof. The metal component contained in the metal layer may besingle metal element.

A known film formation method can be used for forming a multilayer filmincluding a metal layer. From the viewpoint of easiness of filmformation, film formation may be performed by vapor deposition. That is,the metal layer may be a vapor deposited film of a metal component. Thevapor deposited film means a film formed by vapor deposition. In thepresent disclosure and the present description, “vapor deposition” isinclusive of a dry method such as a vacuum vapor deposition method, anion plating method, a sputtering method, or the like. In the vacuumdeposition method, an ion beam assist method in which an ion beam issimultaneously radiated during vapor deposition may be used. The sameapplies to the formation of a high refractive index layer and a lowrefractive index layer described below.

The metal layer included in the multilayer film including a metal layerhas a film thickness of 1.0 nm to 10.0 nm. Hereinafter, the metal layerhaving a film thickness of 1.0 nm to 10.0 nm is also simply referred toas a metal layer. From the viewpoint of transmittance (for example,luminous transmittance) of the spectacle lens, the thickness of themetal layer may be 9.0 nm or less, 8.0 nm or less, 7.0 nm or less, 6.0nm or less, 5.0 nm or less, 4.0 nm or less, or 3.0 nm or less. Inaddition, from the viewpoint of absorption efficiency of blue light orthe like by the metal layer, the thickness of the metal layer is 1.0 nmor more, and may be 1.1 nm or more. Only one metal layer with a filmthickness of 1.0 nm to 10.0 nm may be included in the multilayer filmincluding a metal layer, but in one embodiment, the metal layer may bedivided into two or more layers and another layer may be present betweenthe divided layers. In this case, the total film thickness of the metallayers divided into two or more layers is 1.0 nm to 10.0 nm.

The multilayer film including a metal layer may be a multilayer film inwhich a metal layer is included in a multilayer film in which a highrefractive index layer and a low refractive index layer are alternatelylaminated. In the present disclosure and the present description, theterms “high” and “low” relating to “high refractive index” and “lowrefractive index” are relative expressions. That is, the high refractiveindex layer means a layer having a refractive index higher than that ofthe low refractive index layer included in the same multilayer film. Inother words, the low refractive index layer is a layer having arefractive index lower than that of the high refractive index layerincluded in the same multilayer film. The refractive index of the highrefractive index material constituting the high refractive index layercan be, for example, 1.60 or more (for example, a range of 1.60 to2.40), and the refractive index of the low refractive index materialconstituting the low refractive index layer can be, for example, 1.59 orless (for example, a range of 1.37 to 1.59). However, as describedabove, since the expressions “high” and “low” relating to the highrefractive index and the low refractive index are relative, therefractive indexes of the high refractive index material and the lowrefractive index material are not limited to the above ranges.

An inorganic material, an organic material or an organic/inorganiccomposite material can be used as the high refractive index material andthe low refractive index material, and from the viewpoint of filmforming properties and the like. The multilayer film including a metallayer may be an inorganic multilayer film. More specifically, the highrefractive index material for forming the high refractive index layercan be exemplified by one or a mixture of two or more of oxides selectedfrom the group consisting of zirconium oxide (for example, ZrO₂),tantalum oxide (Ta₂O₅), titanium oxide (for example, TiO₂), aluminumoxide (Al₂O₃), yttrium oxide (for example, Y₂O₃), hafnium oxide (forexample, HfO₂), and niobium oxide (for example, Nb₂O₅). Meanwhile, thelow refractive index material for forming the low refractive index layercan be exemplified by one or a mixture of two or more of oxides orfluorides selected from the group consisting of silicon oxide (forexample, SiO₂), magnesium fluoride (for example, MgF₂) and bariumfluoride (for example, BaF₂). In the above example, oxides and fluoridesare represented by stoichiometric compositions for convenience sake, butthose having a deficient or excessive amount of oxygen or fluorine withrespect to the stoichiometric composition also can be used as the highrefractive index material or low refractive index material.

The high refractive index layer may be a film including a highrefractive index material as a main component, and the low refractiveindex layer is a film including a low refractive index material as amain component. Here, the main component is a component which is presentin the largest amount in the film, and is usually a component present inan amount of about 50% by mass to 100% by mass, and may be about 90% bymass to 100% by mass with respect to the mass of the film. Such a film(for example, a deposited film) can be formed by performing filmformation using a film forming material (for example, a vapor depositionsource) including the high refractive index material or the lowrefractive index material as the main component. The main componentrelating to the film forming material is also the same as describedabove. The film and the film-forming material sometimes includeimpurities inevitably admixed thereto, and also may include othercomponents within ranges such that the function of the main component isnot impaired, for example, other inorganic substances and well-knownadditional components playing the role of assisting film formation. Filmformation can be performed by a known film formation method, and fromthe viewpoint of easiness of film formation, vapor deposition may beused.

The multilayer film including a metal layer can be, for example, amultilayer film in which a total of 3 to 10 of high refractive indexlayers and low refractive index layers are alternately laminated. Thefilm thickness of the high refractive index layer and the film thicknessof the low refractive index layer can be determined according to thelayer configuration. Specifically, the combination of the layers to beincluded in the multilayer film and the film thickness of each layer canbe determined by optical simulation by a known method based on therefractive indexes of the film forming materials for forming the highrefractive index layer and the low refractive index layer and thedesired reflection characteristic and transmission characteristic wishedto be imparted to the spectacle lens by providing he multilayer film.

The layer configuration of the multilayer film including a metal layercan be exemplified by:

a first layer (low refractive index layer)/a second layer (highrefractive index layer)/a third layer (low refractive index layer)/afourth layer (high refractive index layer)/a fifth layer (low refractiveindex layer)/a sixth layer (high refractive index layer)/a seventh layer(metal layer)/an eighth layer (low refractive index layer), from thelens substrate side toward the lens outermost surface side.

In the above example of the layer configuration, the notation “/” ismeant to be inclusive of the case in which the layer on the left and thelayer on the right of “/” are adjacent to each other, and the case inwhich a conductive oxide layer described below is present between thelayer on the left and the layer on the right of “/”.

As an example of a combination of the low refractive index layer and thehigh refractive index layer contained in the multilayer film including ametal layer, a combination of a film including silicon oxide as a maincomponent (low refractive index layer) and a film including zirconiumoxide as a main component (high refractive index layer) can bementioned. Further, a combination of a film including silicon oxide as amain component (low refractive index layer) and a film including niobiumoxide as a main component (a high refractive index layer) can also bementioned. A multilayer film including at least one laminated structurehaving two layers of the above combination adjacent to each other can beexemplified as an example of a multilayer film including a metal layer.

In addition to the metal layer, the high refractive index layer and thelow refractive index layer described above, the multilayer filmincluding a metal layer can also include a layer including a conductiveoxide as a main component (conductive oxide layer), or one or morelayers of a vapor-deposited film of a conductive oxide formed by vapordeposition using a vapor deposition source having the conductive oxideas a main component, at a random position in the multilayer film. Thisalso applies to other multilayer films. The main component describedwith respect to the conductive oxide layer is also the same as describedabove.

From the viewpoint of transparency of the spectacle lens, an indium tinoxide (tin-doped indium oxide (ITO)) layer having a thickness of 10.0 nmor less, a tin oxide layer having a thickness of 10.0 nm or less, andthe conductive oxide layer may be a titanium oxide layer having athickness of 10.0 nm or less. The indium tin oxide (ITO) layer is alayer including ITO as a main component. This also applies to the tinoxide layer and the titanium oxide layer. By including the conductiveoxide layer in the multilayer film including a metal layer and the othermultilayer film, it is possible to prevent the spectacle lens from beingelectrically charged and also to prevent dust and dirt from adheringthereto. In the present disclosure and present description, an indiumtin oxide (ITO) layer having a thickness of 10.0 nm or less, a tin oxidelayer having a thickness of 10.0 nm or less, and a titanium oxide layerhaving a thickness of 10.0 nm or less are not considered as the “metallayer”, “high refractive index layer” or “low refractive index layer”included in the multilayer film including a metal layer and anothermultilayer film. That is, even when one or more of these layers arecontained in the multilayer film including a metal layer or anothermultilayer film, these layers shall not be considered as the “metallayer”, “high refractive index layer” or “low refractive index layer”.The thickness of the conductive oxide layer having a thickness of 10.0nm or less can be, for example, 0.1 nm or more.

(Other Multilayer Film)

In the case where the spectacle lens has a multilayer film including ametal layer on one of the object-side surface and the eyeball-sidesurface and another multilayer film on the other surface, the othermultilayer film can be exemplified by a multilayer film having aproperty of strongly reflecting blue light and a multilayer film that isusually provided as an antireflection film on a spectacle lens. Theantireflection film can be exemplified by a multilayer film exhibitingan antireflection effect against visible light (light in a wavelengthrange of 380 nm to 780 nm). The other multilayer film can be, forexample, an inorganic multilayer film. Configurations of a multilayerfilm having a property of strongly reflecting blue light and amultilayer film functioning as an antireflection film are well known.For example, the other multilayer film can be exemplified by amultilayer film in which a total of three to ten layers of a highrefractive index layer and a low refractive index layer are alternatelylaminated. Details of the high refractive index layer and the lowrefractive index layer are as described above. For example, in the casewhere a multilayer film including a metal layer is provided on theeyeball-side surface of the lens substrate, by providing a multilayerfilm having a property of strongly reflecting blue light on theobject-side surface, it is possible to set the blue light reflectance onthe object-side surface that is obtained by measurement from the objectside of the spectacle lens to the range of 15.0% to 25.0%. The layerconfiguration of such a multilayer film can be exemplified by:

a configuration in which a first layer (low refractive index layer)/asecond layer (high refractive index layer)/a third layer (low refractiveindex layer)/a fourth layer (high refractive index layer)/a fifth layer(low refractive index layer)/a sixth layer (high refractive indexlayer)/a seventh layer (low refractive index layer) are laminated inthis order;

a configuration in which a first layer (high refractive index layer)/asecond layer (low refractive index layer)/a third layer (high refractiveindex layer)/a fourth layer (low refractive index layer)/a fifth layer(high refractive index layer)/a sixth layer (low refractive index layer)are laminated in this order; and

a configuration in which a first layer (low refractive index layer)/asecond layer (high refractive index layer)/a third layer (low refractiveindex layer)/a fourth layer (high refractive index layer)/a fifth layer(low refractive index layer) are laminated in this order.

Further, as an example of a combination of the low refractive indexlayer and the high refractive index layer contained in anothermultilayer film, a combination of a film including silicon oxide as amain component (low refractive index layer) and a film includingzirconium oxide as a main component (high refractive index layer) can bementioned. Further, a combination of a film including a silicon oxide asa main component (low refractive index layer) and a film including aniobium oxide as a main component (high refractive index layer) can alsobe mentioned. A multilayer film including at least one laminatedstructure having two layers of the above combination adjacent to eachother can be exemplified as an example of another multilayer film.

Further, another functional film can be formed on the multilayer filmincluding a metal layer and/or another multilayer film. Such afunctional film can be exemplified by various functional films such as awater repellent or hydrophilic antifouling film, an anti-fog film andthe like. For these functional films, well-known techniques can beapplied.

<Various Characteristics of Spectacle Lens>

(Luminous Transmittance)

In one embodiment, the spectacle lens can be a spectacle lens havinghigh luminous transmittance and excellent transparency. The luminoustransmittance of the spectacle lens is, for example, 35.0% or more, maybe 40.0% or more, 45.0% or more, 50.0% or more, 55.0% or more, 60.0% ormore, 65.0% or more, 70.0% or more, 75.0% or more, 80.0% or more, or85.0% or more. Further, the luminous transmittance of the spectacle lensis, for example, 95.0% or less and can be 90.0% or less. By making themetal layer included in the multilayer film including a metal layer as athin film (more specifically, a film thickness of 1.0 nm to 10.0 nm), itis possible to realize the above-described blue light cut ratio withoutsignificantly lowering the luminous transmittance.

(Luminous Reflectance)

From the viewpoint of improving the appearance quality of the spectaclelens, the luminous reflectance measured on the object-side surface ofthe spectacle lens may be low. From the viewpoint of further improvingthe wearing feeling of the spectacle lens, the luminous reflectancemeasured on the eyeball-side surface of the spectacle lens may be low.From the viewpoint of improving the appearance quality, the luminousreflectance on the object-side surface obtained by measurement from theobject side of the spectacle lens may be 2.00% or less, 1.80% or less,1.50% or less, or 1.30% or less. Meanwhile, from the viewpoint offurther improving the wearing feeling, the luminous reflectance on theeyeball-side surface obtained by measurement from the eyeball side ofthe spectacle lens may be 2.00% or less, 1.80% or less, 1.50% or less,or 1.30% or less.

The luminous reflectance on the object-side surface obtained bymeasurement from the object side of the spectacle lens and the luminousreflectance on the eyeball-side surface obtained by measurement from theeyeball side of the spectacle lens each can be, for example, 0.10% ormore, 0.20% or more, 0.30% or more, 0.40% or more, or 0.50% or more, butthe lower limits presented hereinabove are exemplary and not limiting.The luminous reflectance can be realized by designing the multilayerfilm including a metal layer or other multilayer film provided on theobject-side surface and/or the eyeball-side surface of the lenssubstrate. The film can be designed by optical simulation by a knownmethod.

(YI Value)

Since the spectacle lens exhibits a blue light cut ratio of 35.0% ormore, it is possible to reduce the quantity of blue light incident onthe eyes of the spectacle wearer. In this regard, where a multilayerfilm having the property of selectively and strongly reflecting bluelight is provided on both surfaces of the lens substrate, although it ispossible to increase the blue light cut ratio of the spectacle lens, thevisual field of the spectacle wearer tends to become yellowish(hereinafter also simply referred to as “yellowness”). This is becausesince the ratio of green light and red light relatively increases asblue light in the light of various wavelengths in the visible range iscut off, the yellowness of mixed color of red and green is easilyvisible. Meanwhile, the spectacle lens according to one aspect of thepresent disclosure can reduce the yellowness while exhibiting a bluelight cut ratio of 35.0% or more. Metals have a property of absorbinglight in the visible range. Therefore, the multilayer film including ametal layer which is included in the spectacle lens can absorb not onlyblue light but also green light, red light and the like due to the metallayer. It is conceivable that this contributes to suppressing yellownessof the visual field of spectacle wearer while realizing a blue light cutratio of 35.0% or more. The spectacle lens can exhibit a YI value of27.0% or less. The YI value may be 26.0% or less, or 25.0% or less.Further, the YI value can be, for example, 15.0% or more or 20.0% ormore, but YI value may be lower because the yellowness is reduced.Therefore, the above-exemplified lower limit may be exceeded.

(Main Wavelength)

The spectacle lens has a blue light reflectance of 15.0% to 25.0% on theobject-side surface obtained by measurement from the object side of thespectacle lens and has the property of strongly reflecting blue light onthe object-side surface. The main wavelength on the object-side surfaceobtained by measurement from the object side of such a spectacle lenscan be in the range of 400.0 nm to 500.0 nm which is the wavelengthrange of blue light.

Meanwhile, from the viewpoint of improving the appearance quality of thespectacle lens, there may be no significant difference between the mainwavelengths measured on both surfaces of the spectacle lens. From thisviewpoint, the main wavelength on the eyeball-side surface measured fromthe object side of the spectacle lens may be also in the range of 400.0nm to 500.0 nm.

From the viewpoint of further improving the wearing feeling of thespectacle lens, the main wavelengths on both surfaces determined bymeasurement from the eyeball side of the spectacle lens may not differgreatly. From this viewpoint, the main wavelength on the object-sidesurface obtained by measurement from the eyeball side of the spectaclelens and the main wavelength on the eyeball-side surface obtained bymeasurement from the eyeball side may be also in the range of 400.0 nmto 500.0 nm.

Each of the above main wavelengths can be, for example, 410.0 nm or moreor 420.0 nm or more, and can be, for example, 490.0 nm or less or 485.0nm or less.

Regarding the main wavelength, when comparing the case where the metallayer is located close to the lens substrate and the case where themetal layer is located far from the lens substrate, when the metal layeris located farther from the lens substrate, the main wavelength tends tobe on the shorter wavelength side.

[Spectacles]

A further aspect of the present disclosure relates to spectaclesincluding the spectacle lens according to one aspect of the presentdisclosure. Details of the spectacle lens included in the spectacles areas described above. By providing the spectacles with such a spectaclelens, it is possible to reduce the burden of blue light on the eyes ofthe spectacle wearer. Further, because of the spectacle lens provided tothe spectacles, the intensity with which the ghost (double image) formedby multiple reflection of the blue light inside the spectacle lens isvisually perceived can be reduced or the intensity can be reduced so asnot to be visually recognizable. There are no particular restrictions onthe configuration of the spectacles such as a frame, and publicly knowntechniques can be used.

EXAMPLES

Hereinafter, the present disclosure will be further described withreference to Examples. However, the present disclosure is not limited tothe embodiment shown in the Examples

Example 1 (1) Preparation of Lens Substrate (Lens Substrate A) IncludingBlue Light Absorbing Compound

A total of 100.00 parts by mass of bis-(β-epithiopropyl) sulfide and0.40 parts by mass of2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole arestirred and mixed, and then 0.05 parts by mass oftetra-n-butylphosphonium bromide as a catalyst was added thereto,followed by stirring and mixing under reduced pressure of 10 mmHg for 3min to prepare a monomer composition for a lens (curable composition).Subsequently, the monomer composition for a lens was poured into a lensmolding mold (0.00 D, wall thickness 2.0 mm) configured of a glass moldand a resin gasket prepared in advance, and polymerization was carriedout in an electric furnace with a temperature inside the furnace of 20°C. to 100° C. over 20 h. After completion of the polymerization, thegasket and the mold were removed, and then heat treatment was performedat 110° C. for 1 h to obtain a plastic lens (lens substrate A). Theobtained lens substrate A had a convex surface on the object side, aconcave surface on the eyeball side, and a refractive index of 1.60.

(2) Deposition of Multilayer Film

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 1 (Table 1-1, Table 1-2) were prepared by ion-assisted vapordeposition on the surface of the hard coat layer on the object side andon the surface of the hard coat layer on the eyeball side, respectively,by using oxygen gas and nitrogen gas as assist gases.

In this manner, the spectacle lens of Example 1 having a multilayer filmincluding a metal layer (chromium (metallic Cr) layer) on the eyeballside and another multilayer film (not including a metal layer) on theobject side was obtained.

In this Example, for both the convex side and the concave side, themultilayer vapor-deposited film was formed by lamination in the order ofthe first layer, the second layer, . . . from the lens substrate side(hard coat layer side) toward the front side of the spectacle lens, sothat the outermost layer on the spectacle lens surface side was thelayer indicated in the lowermost row in Table 1. In addition, in thisExample, the film was formed by using evaporation sources (filmformation materials) made of oxides shown in Table 1 or chromium(metallic Cr), except for impurities that could be unavoidably admixed.Therefore, the metal layer formed here is a chromium layer (metallic Crlayer). Table 1 shows the refractive index of each oxide and the filmthickness of each layer. The same applies also to Examples andComparative Examples which will be described later.

Example 2

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 2 (Table 2-1, Table 2-2) were prepared by ion-assisted vapordeposition on the surface of the hard coat layer on the object side andon the surface of the hard coat layer on the eyeball side, respectively,by using oxygen gas and nitrogen gas as assist gases.

In this manner, the spectacle lens of Example 2 having a multilayer filmincluding a metal layer (chromium (metallic Cr) layer) on the eyeballside and another multilayer film (not including a metal layer) on theobject side was obtained.

Example 3

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 3 (Table 3-1, Table 3-2) were prepared by ion-assisted vapordeposition on the surface of the hard coat layer on the object side andon the surface of the hard coat layer on the eyeball side, respectively,by using oxygen gas and nitrogen gas as assist gases.

In this manner, the spectacle lens of Example 3 having a multilayer filmincluding a metal layer (chromium (metallic Cr) layer) on the eyeballside and another multilayer film (not including a metal layer) on theobject side was obtained.

Example 4

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 4 (Table 4-1, Table 4-2) were prepared by ion-assisted vapordeposition on the surface of the hard coat layer on the object side andon the surface of the hard coat layer on the eyeball side, respectively,by using oxygen gas and nitrogen gas as assist gases.

In this manner, the spectacle lens of Example 4 having a multilayer filmincluding a metal layer (nickel (metallic Ni) layer) on the eyeball sideand another multilayer film (not including a metal layer) on the objectside was obtained.

Example 5

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 5 (Table 5-1, Table 5-2) were prepared by ion-assisted vapordeposition on the surface of the hard coat layer on the object side andon the surface of the hard coat layer on the eyeball side, respectively,by using oxygen gas and nitrogen gas as assist gases.

In this manner, the spectacle lens of Example 5 having a multilayer filmincluding a metal layer (silver (metallic Ag) layer) on the eyeball sideand another multilayer film (not including a metal layer) on the objectside was obtained.

Example 6

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 6 (Table 6-1, Table 6-2) were prepared by ion-assisted vapordeposition on the surface of the hard coat layer on the object side andon the surface of the hard coat layer on the eyeball side, respectively,by using oxygen gas and nitrogen gas as assist gases.

In this manner, the spectacle lens of Example 6 having a multilayer filmincluding a metal layer (chromium (metallic Cr) layer) on the eyeballside and another multilayer film (not including a metal layer) on theobject side was obtained.

Example 7

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 7 (Table 7-1, Table 7-2) were prepared by ion-assisted vapordeposition on the surface of the hard coat layer on the object side andon the surface of the hard coat layer on the eyeball side, respectively,by using oxygen gas and nitrogen gas as assist gases.

In this manner, the spectacle lens of Example 7 having a multilayer filmincluding a metal layer (chromium (metallic Cr) layer) on the eyeballside and another multilayer film (not including a metal layer) on theobject side was obtained.

Comparative Example 1

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 8 were prepared by ion-assisted vapor deposition on the surface ofthe hard coat layer on the object side and on the surface of the hardcoat layer on the eyeball side, respectively, by using oxygen gas andnitrogen gas as assist gases.

In this manner, the spectacle lens of Comparative Example 1 havinganother multilayer film (not including a metal layer) on the object sideand the eyeball side was obtained.

Comparative Example 2

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 9 were prepared by ion-assisted vapor deposition on the surface ofthe hard coat layer on the object side and on the surface of the hardcoat layer on the eyeball side, respectively, by using oxygen gas andnitrogen gas as assist gases.

In this manner, the spectacle lens of Comparative Example 2 havinganother multilayer film (not including a metal layer) on the object sideand the eyeball side was obtained.

Comparative Example 3

Both surfaces of the lens substrate A were optically processed(polished) to obtain optical surfaces, and then a hard coat layer (curedlayer obtained by curing the curable composition) having a thickness of3000 nm was formed on both surfaces.

Multilayer vapor-deposited films having the configurations shown inTable 10 (Table 10-1, Table 10-2) were prepared by ion-assisted vapordeposition on the surface of the hard coat layer on the object side andon the surface of the hard coat layer on the eyeball side, respectively,by using oxygen gas and nitrogen gas as assist gases.

In this manner, the spectacle lens of Comparative Example 3 having amultilayer film including a chromium layer on the eyeball side andanother multilayer film (not including a chromium layer) on the objectside was obtained.

By contrast with the multilayer film including a chromium layer (thechromium layer is the seventh layer) that is located on the eyeball sideof the spectacle lens of Example 2, the multilayer film including ametal layer that is located on the eyeball side of the spectacle lens ofComparative Example 3 has the metal layer (chromium layer) as the secondlayer.

The film thickness shown in Tables 1 to 10 is a value (unit: nm)obtained by converting the optical film thickness measured by theoptical film thickness measuring device into a physical film thickness.The thickness of each layer was controlled by the deposition time.

TABLE 1-1 Film Refractive Example 1 forming index Object material (500nm) side First SiO₂ 1.46 95.4 layer Second ZrO₂ 2.09 19.6 layer ThirdSiO₂ 1.46 69.8 layer Fourth ZrO₂ 2.09 51.7 layer Fifth SiO₂ 1.46 116.8layer

TABLE 1-2 Film Refractive Example 1 forming index Eyeball material (500nm) side First SiO₂ 1.46 58.7 layer Second ZrO₂ 2.09 2.0 layer ThirdSiO₂ 1.46 132.8 layer Fourth ZrO₂ 2.09 24.7 layer Fifth SiO₂ 1.46 30.5layer Sixth ZrO₂ 2.09 59.6 layer Seventh Cr 1.5 layer Eighth SiO₂ 1.4698.3 layer

TABLE 2-1 Film Refractive Example 2 forming index Object material (500nm) side First SiO₂ 1.46 79.5 layer Second ZrO₂ 2.09 29.0 layer ThirdSiO₂ 1.46 48.7 layer Fourth ZrO₂ 2.09 57.6 layer Fifth SiO₂ 1.46 122.3layer

TABLE 2-2 Film Refractive Example 2 forming index (500 Eyeball materialnm) side First SiO₂ 1.46 80.0 layer Second ZrO₂ 2.09 8.6 layer ThirdSiO₂ 1.46 67.6 layer Fourth ZrO₂ 2.09 32.9 layer Fifth SiO₂ 1.46 26.2layer Sixth ZrO₂ 2.09 65.0 layer Seventh Cr 1.5 layer Eighth SiO₂ 1.4697.0 layer

TABLE 3-1 Film Refractive Example 3 forming index (500 Object materialnm) side First SiO₂ 1.46 79.5 layer Second ZrO₂ 2.09 33.1 layer ThirdSiO₂ 1.46 50.2 layer Fourth ZrO₂ 2.09 58.1 layer Fifth SiO₂ 1.46 127.8layer

TABLE 3-2 Film Refractive Example 3 forming index (500 Eyeball materialnm) side First SiO₂ 1.46 80.0 layer Second ZrO₂ 2.09 8.6 layer ThirdSiO₂ 1.46 67.6 layer Fourth ZrO₂ 2.09 27.3 layer Fifth SiO₂ 1.46 30.9layer Sixth ZrO₂ 2.09 57.2 layer Seventh Cr 1.5 layer Eighth SiO₂ 1.4698.6 layer

TABLE 4-1 Film Refractive Example 4 forming index (500 Object materialnm) side First SiO₂ 1.46 79.5 layer Second ZrO₂ 2.09 30.0 layer ThirdSiO₂ 1.46 48.7 layer Fourth ZrO₂ 2.09 58.1 layer Fifth SiO₂ 1.46 122.3layer

TABLE 4-2 Film Refractive Example 4 forming index (500 Eyeball materialnm) side First SiO₂ 1.46 80.0 layer Second ZrO₂ 2.09 8.6 layer ThirdSiO₂ 1.46 67.6 layer Fourth ZrO₂ 2.09 32.9 layer Fifth SiO₂ 1.46 26.2layer Sixth ZrO₂ 2.09 65.0 layer Seventh Ni 1.5 layer Eighth SiO₂ 1.4697.0 layer

TABLE 5-1 Film Refractive Example 5 forming index (500 Object materialnm) side First SiO₂ 1.46 79.5 layer Second ZrO₂ 2.09 30.0 layer ThirdSiO₂ 1.46 48.7 layer Fourth ZrO₂ 2.09 58.1 layer Fifth SiO₂ 1.46 122.3layer

TABLE 5-2 Film Refractive Example 5 forming index (500 Eyeball materialnm) side First SiO₂ 1.46 80.0 layer Second ZrO₂ 2.09 8.6 layer ThirdSiO₂ 1.46 67.6 layer Fourth ZrO₂ 2.09 32.9 layer Fifth SiO₂ 1.46 26.2layer Sixth ZrO₂ 2.09 65.0 layer Seventh Ag 1.8 layer Eighth SiO₂ 1.4697.0 layer

TABLE 6-1 Film Refractive Example 6 forming index (500 Object materialnm) side First SiO₂ 1.46 79.5 layer Second ZrO₂ 2.09 30.0 layer ThirdSiO₂ 1.46 48.7 layer Fourth ZrO₂ 2.09 58.1 layer Fifth SiO₂ 1.46 122.3layer

TABLE 6-2 Film Refractive Example 6 forming index (500 Eyeball materialnm) side First SiO₂ 1.46 46.4 layer Second ZrO₂ 2.09 16.6 layer ThirdSiO₂ 1.46 52.5 layer Fourth ZrO₂ 2.09 31.0 layer Fifth SiO₂ 1.46 30.9layer Sixth ZrO₂ 2.09 64.1 layer Seventh Cr 5.0 layer Eighth SiO₂ 1.4694.2 layer

TABLE 7-1 Film Refractive Example 7 forming index (500 Object materialnm) side First SiO₂ 1.46 79.5 layer Second ZrO₂ 2.09 30.0 layer ThirdSiO₂ 1.46 48.7 layer Fourth ZrO₂ 2.09 58.1 layer Fifth SiO₂ 1.46 122.3layer

TABLE 7-2 Film Refractive Example 7 forming index (500 Eyeball materialnm) side First SiO₂ 1.46 54.1 layer Second ZrO₂ 2.09 20.1 layer ThirdSiO₂ 1.46 37.5 layer Fourth ZrO₂ 2.09 41.8 layer Fifth SiO₂ 1.46 35.0layer Sixth ZrO₂ 2.09 74.7 layer Seventh Cr 10.0 layer Eighth SiO₂ 1.465.7 layer

TABLE 8 Refractive Comparative Film index Example 1 forming (500 ObjectEyeball material nm) side side First SiO₂ 1.46 122.0 81.9 layer SecondZrO₂ 2.09 16.4 25.9 layer Third SiO₂ 1.46 54.8 44.4 layer Fourth ZrO₂2.09 61.2 86.3 layer Fifth SiO₂ 1.46 115.1 102.2 layer

TABLE 9 Refractive Comparative Film index Example 2 forming (500 ObjectEyeball material nm) side side First SiO₂ 1.46 178.7 178.7 layer SecondZrO₂ 2.09 18.5 18.5 layer Third SiO₂ 1.46 30.9 30.9 layer Fourth ZrO₂2.09 91.4 91.4 layer Fifth SiO₂ 1.46 98.8 98.8 layer

TABLE 10-1 Refractive Comparative Film index Example 3 forming (500Object material nm) side First SiO₂ 1.46 79.5 layer Second ZrO₂ 2.0929.0 layer Third SiO₂ 1.46 48.7 layer Fourth ZrO₂ 2.09 57.6 layer FifthSiO₂ 1.46 122.3 layer

TABLE 10-2 Refractive Comparative Film index Example 3 forming (500Eyeball material nm) side First SiO₂ 1.46 80.0 layer Second Cr 1.5 layerThird ZrO₂ 2.09 8.6 layer Fourth SiO₂ 1.46 67.6 layer Fifth ZrO₂ 2.0932.9 layer Sixth SiO₂ 1.46 26.2 layer Seventh ZrO₂ 2.09 65.0 layerEighth SiO₂ 1.46 97.0 layer

[Evaluation Methods]

<1. Blue Light Cut Ratio and Luminous Transmittance of Spectacle Lens>

The direct incidence transmission spectral characteristics of eachspectacle lens of Examples and Comparative Examples were measured with aspectrophotometer U4100 manufactured by Hitachi, Ltd. at a pitch of 1 nmfrom a wavelength of 380 nm to 780 nm by causing the light to fall fromthe surface side (convex side) on the object side of the spectacle lenson the optical center on the object-side surface.

Using the measurement results, the blue light cut ratio and luminoustransmittance were determined by the methods described above.

<2. Blue Light Reflectance Measured on Object-Side Surface andEyeball-Side Surface of Spectacle Lens>

The direct incidence reflection spectral characteristics at the opticalcenter were measured on the object-side surface (convex surface side)and the eyeball-side surface (concave surface side) from the object sideof each spectacle lens of Examples and Comparative Examples.

Using the measurement results, the average reflectance (blue lightreflectance) on the object-side surface and the eyeball-side surfacemeasured from the object side in the wavelength range of 400 nm to 500nm was determined by the method described above.

Further, the direct incidence reflection spectral characteristics at theoptical center were measured on the object-side surface (convex surfaceside) and the eyeball-side surface (concave surface side) from theeyeball side of each spectacle lens of Examples and ComparativeExamples.

Using the measurement results, the average reflectance (blue lightreflectance) on the object-side surface and the eyeball-side surfacemeasured from the eyeball side in the wavelength range of 400 nm to 500nm was determined by the method described above.

The above measurements were carried out using a lens reflectancemeasuring instrument USPM-RU manufactured by Olympus Corporation(measuring pitch: 1 nm). At the time of measurement, the focal positionwas adjusted to the surface to be measured by adjusting the height ofthe sample stand of the spectrophotometer.

The reflection spectroscopic spectrum (measured from the object side)obtained for the spectacle lens of Example 1 is shown in FIG. 1, and thereflection spectroscopic spectrum (measured from the object side)obtained for the spectacle lens of Example 2 is shown in FIG. 2.

<3. Luminous Reflectance>

Using the measurement results of the direct incidence reflectionspectroscopic characteristic on the object-side surface measured fromthe object side that were obtained in 2. hereinabove, the luminousreflectance on the object-side surface obtained by measurement from theobject side was determined by the method described above.

Using the measurement result of the direct incidence reflectionspectroscopic characteristic on the eyeball-side surface measured fromthe eyeball side that were obtained in 2. hereinabove, the luminousreflectance on the eyeball-side surface obtained by measurement from theeyeball side was determined by the method described above.

<4. Main Wavelength>

The main wavelength on the object-side surface obtained by measurementfrom the object side of the spectacle lens was obtained according toAnnex JA of JIS Z 8781-3:2016 by using the measurement result of thedirect incident reflection spectroscopic characteristic obtained on theobject-side surface by measurement from the object side of the spectaclelens in 2. hereinabove.

The main wavelength on the eyeball-side surface obtained by measurementfrom the object side of the spectacle lens was obtained according toAnnex JA of JIS Z 8781-3:2016 by using the measurement result of thedirect incident reflection spectroscopic characteristic obtained on theeyeball-side surface by measurement from the object side of thespectacle lens in 2. hereinabove.

The main wavelength on the object-side surface obtained by measurementfrom the eyeball side of the spectacle lens was obtained according toAnnex JA of JIS Z 8781-3:2016 by using the measurement result of thedirect incident reflection spectroscopic characteristic obtained on theobject-side surface by measurement from the eyeball side of thespectacle lens in 2. hereinabove.

The main wavelength on the eyeball-side surface obtained by measurementfrom the eyeball side of the spectacle lens was obtained according toAnnex JA of JIS Z 8781-3:2016 by using the measurement result of thedirect incident reflection spectroscopic characteristic obtained on theeyeball-side surface by measurement from the eyeball side of thespectacle lens in 2. hereinabove.

<5. Ghost Evaluation>

Each of the spectacle lenses of Examples and Comparative Examples wasobserved from the eyeball side at a position of 30 cm below afluorescent lamp in a dark room, and the presence or absence and degreeof occurrence of a ghost (double image) were sensory-evaluated based onthe following evaluation criteria.

A+: No ghost is observed. Or a thin ghost is observed, but the ghost ismilder than in A.

A: No clear ghost is observed. A thin ghost is observed.

B: A clear ghost is observed.

<YI Value>

Using the measurement result of the direct incidence transmissionspectroscopic characteristics obtained in 1. hereinabove, the YI valuewas obtained according to JIS K 7373:2006. Specifically, X, Y, and Zwere calculated from the transmission spectrum obtained by measurementof the direct incidence transmission spectroscopic characteristicsaccording to the formula (3) of JIS Z 8701:1999, and the YI value forthe D65 light source was calculated from the calculation formula inSection 6.1 of JIS K 7373:2006.

The above results are shown in Table 11.

TABLE 11 Example Example Example Example Example Example 1 2 3 4 5 6Blue light absorbing compound on lens Present Present Present PresentPresent Present substrate Multilayer film including metal layer PresentPresent Present Present Present Present Blue light cut ratio 39.7% 41.0%44.43% 38.08% 35.01% 54.95% Blue light Object side 17.45% 18.77% 24.67%19.17% 19.17% 19.17% reflectance (measurement from object side) Eyeballside 4.15% 3.10% 3.69% 3.40% 3.24% 10.14% (measurement from eyeballside) Object side 9.40% 10.20% 14.15% 10.19% 10.19% 10.19% (measurementfrom eyeball side) Eyeball side 0.46% 0.70% 0.67% 0.95% 1.34% 1.92%(measurement from object side) Main Object side 458.5 nm 458.0 nm 461.2nm 457.4 nm 457.4 nm 457.4 nm wavelength (measurement from object side)Eyeball side 471.1 nm 469.7 nm 466.4 nm 468.1 nm 470.6 nm 471.7 nm(measurement from eyeball side) Object side 461.7 nm 461.3 nm 464.6 nm460.9 nm 460.9 nm 460.9 nm (measurement from eyeball side) Eyeball side481.4 nm 483.4 nm 477.3 nm 477.1 nm 478.9 nm 482.5 nm (measurement fromobject side) Luminous transmittance 86.7% 85.9% 85.0% 89.2% 93.4% 67.6%Luminous Object side 0.99% 1.27% 1.91% 1.12% 1.12% 1.12% reflectanceEyeball side 0.78% 0.70% 0.74% 0.61% 0.66% 4.62% Ghost evaluation A+ A+A+ A+ A+ A+ YI value 23.5% 24.4% 28.7% 22.8% 23.0% 26.7% Comp. Comp.Comp. Example Example Example Example 7 1 2 3 Blue light absorbingcompound on lens Present Present Present Present substrate Multilayerfilm including metal layer Present Absent Absent Present Blue light cutratio 75.89% 39.5% 23.5% 40.4% Blue light Object side 19.17% 16.71%3.59% 18.77% reflectance (measurement from object side) Eyeball side39.95% 15.54% 5.16% 1.09% (measurement from eyeball side) Object side10.19% 9.32% 2.35% 10.20% (measurement from eyeball side) Eyeball side1.48% 9.27% 3.40% 2.66% (measurement from object side) Main Object side457.4 nm 457.8 nm 468.3 nm 458.0 nm wavelength (measurement from objectside) Eyeball side 488.3 nm 457.7 nm 467.9 nm 492.2 nm (measurement fromeyeball side) Object side 460.9 nm 460.4 nm 470.1 nm 461.3 nm(measurement from eyeball side) Eyeball side 480.7 nm 460.8 nm 469.7 nm−544.9 nm  (measurement from object side) Luminous transmittance 35.4%93.8% 94.4% 85.4% Luminous Object side 1.12% 0.95% 0.52% 1.27%reflectance Eyeball side 39.15% 0.90% 0.75% 0.65% Ghost evaluation A+ BA+ B YI value 26.5% 29.1% 10.4% 24.2%

In Table 11, in the spectacle lens of Comparative Example 2, the bluelight cut ratio is lower than 35.0%. Meanwhile, the spectacle lens ofComparative Example 1 shows a blue light cut ratio higher than that ofthe spectacle lens of Comparative Example 2. However, in the spectaclelens of Comparative Example 1, the ghost evaluation result was B. Thisis conceivably because the blue light reflectance on the eyeball-sidesurface obtained by measurement from the object side of the spectaclelens is 2.00% or more.

By contrast with the multilayer film including a metal layer that islocated on the eyeball side of the spectacle lens of Example 2 havingthe metal layer (chromium layer) as the seventh layer, in the spectaclelens of Comparative Example 3, the multilayer film including a metallayer that is located on the eyeball side has the metal layer (chromiumlayer) as the second layer. This is presumed to be the reason why theblue light reflectance on the eyeball-side surface obtained bymeasurement from the object side of the spectacle lens of ComparativeExample 3 is 2.00% or more, which is conceivably why the ghostevaluation result of the spectacle lens of Comparative Example 3 was B.

Meanwhile, the results shown in Table 11 can confirm that although thespectacle lenses of Examples 1 to 7 showed a high blue light cut ratioof 35.0% or more, the occurrence of a ghost was suppressed.

Further, based on the measured values of each blue light reflectanceshown in Table 11, it can be confirmed that for the object-side surfaceof the spectacle lens, the blue light reflectance obtained bymeasurement from the object side is different from the blue lightreflectance obtained by measurement from the eyeball side. The sameapplies to the blue light reflectance measured on the eyeball-sidesurface of the spectacle lens.

From the viewpoint of reducing the quantity of blue light entering theeyes of the wearer as a result of reflection of the blue light on theeyeball-side surface of the spectacle lens, this blue light beingincident on the object-side surface of the spectacle lens from behindthe wearer of the spectacles, the blue light reflectance on theeyeball-side surface obtained by measurement from the eyeball side ofthe spectacle lens may be 5.00% or less. The blue light reflectance maybe, for example, less than 2.00%, and may be lower than this.

Further, from the viewpoint of reducing the quantity of blue light thatfalls on the spectacle lens from behind the wearer of the spectacles, isreflected on the eyeball-side surface, without being reflected on theobject-side surface, outgoes from the object-side surface and enters theeyes of the wearer, the blue light reflectance on the object-sidesurface obtained by measurement from the eyeball side of the spectaclelens may be 15.00% or less, or 12.00% or less. The blue lightreflectance may be, for example, 5.00% or less, and may be lower thanthis.

Finally, the above-described embodiments are summarized.

According to one aspect, there is provided a spectacle lens having alens substrate including a blue light absorbing compound, and amultilayer film including a metal layer having a film thickness of 1.0nm to 10.0 nm, wherein a blue light cut ratio is 35.0% or more, anaverage reflectance in a wavelength range of 400 nm to 500 nm on anobject-side surface obtained by measurement from the object side is in arange of 15.00% to 25.00%, and an average reflectance in a wavelengthrange of 400 nm to 500 nm on an eyeball-side surface obtained bymeasurement from the object side is less than 2.00%.

The spectacle lens can reduce the burden on the eyes caused by bluelight and can give the wearer of the spectacles provided with thisspectacle lens a satisfactory wearing feeling.

In one embodiment, a main wavelength at an object-side surface that isobtained by measurement from the object side of the spectacle lens is ina range of 400.0 nm to 500.0 nm.

In one embodiment, a main wavelength at an eyeball-side surface that isobtained by measurement from the object side of the spectacle lens is ina range of 400.0 nm to 500.0 nm.

In one embodiment, the main wavelength on the object-side surface thatis obtained by measurement from the object side of the spectacle lensand the main wavelength on the eyeball-side surface that is obtained bymeasurement from the object side are each in a range of 400.0 to 500.0nm.

In one embodiment, the YI value of the spectacle lens is 27.0% or less.

In one embodiment, in the spectacle lens, a multilayer film is locatedon the object-side surface and the eyeball-side surface of the lenssubstrate, and the multilayer film including a metal layer is amultilayer film located on the eyeball-side surface of the lenssubstrate.

In one embodiment, the metal layer is a chromium layer.

In one embodiment, the metal layer is a nickel layer.

In one embodiment, the metal layer is a silver layer.

In one embodiment, the luminous transmittance of the spectacle lens is80.0% or more.

According to another aspect, there is provided a pair of spectaclesincluding the spectacle lens.

Two or more of the various embodiments disclosed in this description canbe arbitrarily combined.

It should be considered that the embodiments disclosed hereinabove areexemplary in all respects and are not restrictive. The scope of thepresent disclosure is defined not by the description above but by theclaims, and is intended to be inclusive of all modifications that do notdepart from the scope and meaning of the claims.

The present disclosure can be used in the field of manufacturingspectacle lenses and spectacles.

What is claimed is:
 1. A spectacle lens, comprising: a lens substrateincluding a blue light absorbing compound, and a multilayer filmincluding a metal layer having a film thickness of 1.0 nm to 10.0 nm,wherein a blue light cut ratio is 35.0% or more, an average reflectancein a wavelength range of 400 nm to 500 nm on an object-side surfaceobtained by measurement from the object side is in a range of 15.00% to25.00%, and an average reflectance in a wavelength range of 400 nm to500 nm on an eyeball-side surface obtained by measurement from theobject side is less than 2.00%.
 2. The spectacle lens according to claim1, wherein a main wavelength at an object-side surface that is obtainedby measurement from the object side of the spectacle lens is in a rangeof 400.0 nm to 500.0 nm.
 3. The spectacle lens according to claim 1,wherein a main wavelength at an eyeball-side surface that is obtained bymeasurement from the object side of the spectacle lens is in a range of400.0 nm to 500.0 nm.
 4. The spectacle lens according to claim 1,wherein a multilayer film is located on the object-side surface and theeyeball-side surface of the lens substrate, and the multilayer filmincluding a metal layer is a multilayer film located on the eyeball-sidesurface of the lens substrate.
 5. The spectacle lens according to claim1, wherein the metal layer is a chromium layer.
 6. The spectacle lensaccording to claim 1, wherein the metal layer is a nickel layer.
 7. Thespectacle lens according to claim 1, wherein the metal layer is a silverlayer.
 8. The spectacle lens according to claim 1, wherein a luminoustransmittance is 80.0% or more.
 9. A pair of spectacles comprising thespectacle lens according to claim 1.